【摘要】 针对基于身份双向代理重签名方案需要复杂双线性对运算的问题,利用哈希函数提出了一种无双线性对的基于身份代理重签名方案。在离散对数困难问题的假设下,证明了该方案在自适应性选择消息攻击下是不可伪造的。该方案具有双向性、多用性、透明性和密钥最优性,避免了双线性对运算。与基于身份的双向代理重签名方案——Shao方案相比,所提方案能够有效降低重签名算法的计算复杂度,提高签名验证算法的计算效率。作为该方案的一个延伸,在其基础上构造了一个聚合代理重签名方案,能将同一时间段内的重签名进行聚合,大大降低了通信带宽。更多还原

【Abstract】 The existing identity-based bidirectional proxy re-signature schemes require expensive bilinear pairing operations. Focused on the issue, an identity-based bidirectional proxy re-signature scheme without bilinear pairing was presented by using hash function. Under the assumption of discrete logarithm difficult problem, the proposed proxy resignature scheme was proved secure against forgery under adaptive chosen message attacks. Furthermore, the proposed scheme was bidirectional, versatile, transparent and key optimal,which eliminated the bilinear pairing operations. Compared with the identity-based bidirectional proxy re-signature scheme — Shao scheme, the proposed scheme could reduce the computational complexity of re-signature algorithm and improve the computation efficiency of signature verification algorithm. Based on the proposed scheme, an aggregate proxy re-signature scheme was proposed. The new scheme can aggregate re-signatures only if they are generated in the same time period, which can greatly reduce the communication overhead.更多还原